Add release notes (#13096)

Author: alexcrichton

RELEASES.md

@@ -4,8 +4,71 @@ Unreleased.
 
 ### Added
 
+* The `wasmtime` CLI now supports a `-g` flag which runs a built-in wasm program
+  to host a `gdbstub`-compatible server (can be connected to with LLDB) to debug
+  guest programs.
+  [#12756](https://github.com/bytecodealliance/wasmtime/pull/12756)
+  [#12771](https://github.com/bytecodealliance/wasmtime/pull/12771)
+  [#12856](https://github.com/bytecodealliance/wasmtime/pull/12856)
+  [#12859](https://github.com/bytecodealliance/wasmtime/pull/12859)
+
+* Wasmtime now has experimental support for the `map<K, V>` type in the
+  component model.
+  [#12216](https://github.com/bytecodealliance/wasmtime/pull/12216)
+
+* Wasmtime's C API now supports wasm tag types.
+  [#12763](https://github.com/bytecodealliance/wasmtime/pull/12763)
+  [#12803](https://github.com/bytecodealliance/wasmtime/pull/12803)
+
+* Wasmtime's C API now supports exceptions.
+  [#12861](https://github.com/bytecodealliance/wasmtime/pull/12861)
+
+* Wasmtime's C API has more support for the GC proposal.
+  [#12914](https://github.com/bytecodealliance/wasmtime/pull/12914)
+  [#12915](https://github.com/bytecodealliance/wasmtime/pull/12915)
+  [#12916](https://github.com/bytecodealliance/wasmtime/pull/12916)
+  [#12917](https://github.com/bytecodealliance/wasmtime/pull/12917)
+
+* An initial implementation of the `wasi:tls` proposal for the 0.3.0-draft
+  version has been added.
+  [#12834](https://github.com/bytecodealliance/wasmtime/pull/12834)
+
 ### Changed
 
+* The `demangle` Cargo feature of the `wasmtime` crate is now compatible with
+  `no_std` targets.
+  [#12740](https://github.com/bytecodealliance/wasmtime/pull/12740)
+
+* The `wasmtime-wasi-tls-*` crates are now merged into one crate with feature
+  flags for each backend.
+  [#12780](https://github.com/bytecodealliance/wasmtime/pull/12780)
+
+* Wasmtime now requires Rust 1.92.0 or later to build.
+  [#12828](https://github.com/bytecodealliance/wasmtime/pull/12828)
+
+* The `cranelift-codegen` crate now compiles for `no_std` targets.
+  [#12812](https://github.com/bytecodealliance/wasmtime/pull/12812)
+
+* The `csdb` instruction, a defense-in-depth measure for spectre, is no longer
+  emitted by default on aarch64 to match what peer runtimes are doing. In some
+  situations this is known to provide up to a 6x performance boost on macOS as
+  well.
+  [#12932](https://github.com/bytecodealliance/wasmtime/pull/12932)
+
+### Fixed
+
+* Wasmtime's native DWARF has been improved on aarch64 to support recovering
+  values more frequently.
+  [#12779](https://github.com/bytecodealliance/wasmtime/pull/12779)
+
+* A significant number of minor issues have been fixed throughout this release.
+  In addition to the [security advisories][adv] found by LLMs there have also
+  been a large number of other issues identified as well. Many minor fixes are
+  present in this release for various situations for issues found in this
+  manner.
+
+[adv]: https://bytecodealliance.org/articles/wasmtime-security-advisories
+
 --------------------------------------------------------------------------------
 
 Release notes for previous releases of Wasmtime can be found on the respective